HIV-1 (human immunodeficiency virus-1) infection remains a major medical problem, with an estimated 40 million people infected worldwide at the end of 2005. The number of cases of HIV and AIDS (acquired immunodeficiency syndrome) has risen rapidly. In 2005, approximately 5.0 million new infections were reported, and 3.1 million people died from AIDS. Currently available drugs for the treatment of HIV include nucleoside reverse transcriptase (RT) inhibitors or approved single pill combinations: zidovudine (or AZT or Retrovir®), didanosine (or Videx®), stavudine (or Zerit®), lamivudine (or 3TC or Epivir®), zalcitabine (or DDC or Hivid®), abacavir succinate (or Ziagen®), Tenofovir disoproxil fumarate salt (or Viread®), emtricitabine (or FTC), Combivir® (contains −3TC plus AZT), Trizivir® (contains abacavir, lamivudine, and zidovudine), Epzicom® (contains abacavir and lamivudine), Truvada® (contains Viread® and emtricitabine); non-nucleoside reverse transcriptase inhibitors: nevirapine (or Viramune®), delavirdine (or Rescriptor®) and efavirenz (or Sustiva®), and peptidomimetic protease inhibitors or approved formulations: saquinavir, indinavir, ritonavir, nelfinavir, amprenavir, lopinavir, and Kaletra® (lopinavir and Ritonavir). Each of these drugs can only transiently restrain viral replication if used alone. However, when used in combination, these drugs have a profound effect on viremia and disease progression. In fact, significant reductions in death rates among AIDS patients have been recently documented as a consequence of the widespread application of combination therapy. However, despite these impressive results, 30 to 50% of patients ultimately fail combination drug therapies. Insufficient drug potency, non-compliance, restricted tissue penetration and drug-specific limitations within certain cell types (e.g. most nucleoside analogs cannot be phosphorylated in resting cells) may account for the incomplete suppression of sensitive viruses. Furthermore, the high replication rate and rapid turnover of HIV-1 combined with the frequent incorporation of mutations, leads to the appearance of drug-resistant variants and treatment failures when sub-optimal drug concentrations are present. Therefore, novel anti-HIV agents exhibiting distinct resistance patterns, and favorable pharmacokinetic as well as safety profiles are needed to provide more treatment options. Improved HIV fusion inhibitors and HIV entry coreceptor antagonists are two examples of new classes of anti-HIV agents currently being studied by a number of investigators.
The properties of a class of HIV entry inhibitors called HIV attachment inhibitors has been improved in an effort to obtain compounds with maximized utility and efficacy as antiviral agents. A disclosure describing indoles of which the structure shown below for BMS-705 is representative has been disclosed [Antiviral Indoleoxoacetyl piperazine Derivatives].

Two other compounds, referred to in the literature as BMS-806 and BMS-043 have been described in both the academic and patent art:

Some description of their properties in human clinical trials have been disclosed in literature.
It should be noted that in all three of these structures, a piperazine amide (In these three structures a piperazine phenyl amide) is present and this group is directly attached to an oxoacetyl moiety. The oxoacetyl group is attached at the 3-position of 4-Fluoro indole in BMS-705 and to the 3 position of substituted azaindoles in BMS-806 and BMS-043.
In an effort to obtain improved anti-HIV compounds, later publications described in part, modified substitution patterns on the indoles and azaindoles. Examples of such effort include: (1) novel substituted indoleoxoacetic piperazine derivatives, (2) substituted piperazinyloxoacetylindole derivatives, and (3) substituted azaindoleoxoacetic piperazine derivatives.
Replacement of these groups with other heteraromatics or substituted heteroaroamatics or bicyclic hydrocarbons was also shown to be feasible. Examples include: (1) indole, azaindole and related heterocyclic amidopiperazine derivatives; (2) bicyclo 4.4.0 antiviral derivatives; and (3) diazaindole derivatives.
A select few replacements for the piperazine amide portion of the molecules have also been described in the art and among these examples are (1) some piperidine alkenes; (2) some pyrrolidine amides; (3) some N-aryl or heteroaryl piperazines; (4) some piperazinyl ureas; and (5) some carboline containing compounds.
Antiviral compounds containing piperidine alkenes are contained in the following published patent applications Wang, Tao; et. al. U.S. Pat. Appl. Publ. US 20040186292 A1 and Wang, et. al. U.S. Pat. Appl. Publ. US 20040063744 A1 but are structurally distinct from the compounds in this application.
Method(s) for preparing prodrugs for this class of compounds was disclosed in Prodrugs of Piperazine and Substituted Piperidine Antiviral Agents (Ueda et al., U.S. non-provisional application Ser. No. 11/066,745, filed Feb. 25, 2005 or US20050209246A1 or WO2005090367A1).
A published PCT patent application WO2003103607A1 (Jun. 11, 2003) disclosures an assay useful for assaying some HIV inhibitors.
Several published patent applications describe combination studies with piperazine benzamide inhibitors, for example, US20050215543 (WO2005102328A1), US20050215544 (WO2005102391A1), and US20050215545 (WO2005102392A2).
A publication on new compounds in this class of attachment inhibitors (Jinsong Wang et. al. Org. Biol. Chem. 2005, 3, 1781-1786.) and a patent application on some more remotely related compounds have appeared WO2005/016344 published on Feb. 24, 2005.
Published patent applications WO2005/016344 and WO2005/121094 also describe piperazine derivatives which are HIV inhibitors. The compounds described in these applications are structurally distinct from the compounds of the present disclosure.
Nothing in these references can be construed to disclose or suggest the novel compounds of this disclosure and their use to inhibit HIV infection.